Kj. Hill et al., REACTIVE LIPOSOMES ENCAPSULATING A GLUCOSE OXIDASE-PEROXIDASE SYSTEM WITH ANTIBACTERIAL ACTIVITY, Biochimica et biophysica acta. Biomembranes, 1326(1), 1997, pp. 37-46
Liposomes were prepared from phospholipid mixtures of dipalmitoylphosp
hatidylcholine (DPPC) and phosphatidylinositol (PI), encapsulating the
enzymes glucose oxidase (GO) and GO in combination with horse radish
peroxidase (HRP) by both extrusion (VET) and reverse-phase evaporation
(REV). The optimum level of PI in DPPC/PI liposomes for targeting to
biofilms of the oral bacterium Streptococcus gordonii has been establi
shed. The liposomes were characterised in terms of the content and act
ivity of the encapsulated enzymes. The antibacterial activity of these
'reactive' liposomes arising from hydrogen peroxide and oxyacids in t
he presence of the substrates glucose and iodide ions, after targeting
to the biofilms, were measured both as a function of liposome-biofilm
incubation time and incubation time with the substrates. Bacterial in
hibition increases with both liposome-biofilm and substrate-biofilm in
cubation time and with the extent of enzyme encapsulation. The reactiv
e liposomes also display antibacterial activity in the presence of sal
iva. The reactive liposomes have potential value in the context of ora
l hygiene.